Here are a few ways to create rounded/cornered graphic panels in Photoshop.

Rounded Rectangle Tool (U)
The easiest method is found in the ‘Rounded Rectangle Tool (U)’ on the Toolbar.
Set your desired Foreground Color.

  1. Option One

    1. Activate the Rounded Rectangle Tool (U)
    2. Go to the Options Bar and activate the Shape Layers option
    3. Then to the mid-right of the Options Bar set the Radius integer. This controls the radius of the corners. Explore with other integers for the effect that best suits your design.

  2. Option Two: Multiplier Keys
    Another method is to use the multiplier Options located on the Options Bar for an active Vector Shape.

    Set your desired Foreground Color.

    1. Activate the Ellipse Tool (U
    2. Drag & Draw an Ellipse.
    3. Ctrl/Command+R to enable Rulers & Drag Horizontal/Vertical Guides to the Bounding edges. More importantly to the center of the object.
    4. Switch to the Rectangle Tool (U).
    5. Activate the ‘Add’ modifier for the active shape.
    6. Snap to the center Guide and drag to draw outward snapping to the top & bottom guides as you draw.
    7. Deselect the shape
      Ctrl/Command + H to hide the Guides to preview the new shape.

  3. Option Three: To build on the above shape.

    1. Mouse over the mid Guide.
    2. Hold the Ctrl/Command + Alt/Option keys, then Click once. Vetical Guide becomes Horizontal Guide.
    3. With Rectangle Tool (U) still active, drag & draw downward to snap to the left/right Vertical Guides.
    4. Switch to the Rectangle Tool (U).
    5. Deselect the shape
    6. Ctrl/Command+H to hide the Guides to preview the new shape.

  4. Option Four: Pen Tool (P)/Paths
    Another method is to use the Pen Tool (P) with Options Bar Shape Layers enabled.
    Set your desired Foreground Color.
    Ctrl/Command + ‘ to enable the Grid. Enable ‘View/Snap’.

    As below a simple Click (to Add Anchor Point) followed by Click & Drag (to Add & Convert Anchor Point) snapping to a desired grid line creates smooth curved shapes.